This invention relates to compounds for treating multidrug resistance and methods for their preparation and use. More particularly, this invention relates to compounds that regulate the cellular transport proteins P-glycoprotein or MRP1, or both, which are the proteins believed to be largely responsible for causing multidrug resistance in cancer patients.
xe2x80x9cDrug resistancexe2x80x9d means a circumstance when a disease (e.g., cancer) does not respond to a therapeutic agent. Drug resistance can be intrinsic, which means that the disease has never been responsive to the therapeutic agent, or acquired, which means that the disease ceases responding to the agent or agents to which the disease had previously been responsive. xe2x80x9cMultidrug resistancexe2x80x9d is a type of drug resistance wherein a disease is resistant to a variety of drugs that can be functionally unrelated, structurally unrelated, or both. Multidrug resistance is a problem associated with cancer and other conditions, such as bacterial, viral, protozoal, and fungal diseases.
One cause of multidrug resistance in cancer patients is that many cancer cells express high levels of the transmembrane transport proteins, such as Pleiotropic-glycoprotein (also known as Pgp, P-glycoprotein, gp-170, or MDR1) and MRP1 (see Borst, P., xe2x80x9cMultidrug resistance: A solvable problem?xe2x80x9d Annals of Oncology, 10, suppl. 4, pp. S162-S164 (1999)). In adenosine-triphosphate driven processes, these transport proteins export hydrophobic compounds (such as vinblastine, daunorubicin, doxorubicin, etoposide, vincristine, and TAXOL(copyright), which are cytotoxic drugs useful for treating cancer) from the cell in an effort to protect the cell from harm. The transport proteins remove the compounds from the cell prior to their having a lethal effect on the cell (see Legrand, et. al, xe2x80x9cSimultaneous Activity of MRP1 and Pgp Is Correlated With In Vitro Resistance to Daunorubicin and With In Vivo Resistance in Adult Acute Myeloid Leukemiaxe2x80x9d, Blood, Vol. 94, No. 3, pp. 1046-1056 (1999); and Zhu, B. T.; xe2x80x9cA Novel Hypothesis for the Mechanism of Action of P-glycoprotein as a Multidrug Transporter,xe2x80x9d Molecular Carcinogenesis 25, pp.1-14 (1999)). Although it is not currently known which of these two classes of proteins is more important for multidrug resistance, and indeed it may be that the class (or classes) of protein which is important depends on the type of cancer and the particular drug or drugs used to treat the cancer, Pgp is known to be highly expressed in approximately 50% of human cancers which require drug therapy. Consequently, Pgp is believed to be a major cause of multidrug resistance.
Other types of multidrug resistance, such as antibacterial, antiviral, and antifungal multidrug resistance may also be caused by the action of transport proteins that are similar to Pgp, and others (see xe2x80x9cAnnual Reports on Medicinal Chemistryxe2x80x9433; Section III Cancer and Infectious Diseasesxe2x80x9d ed. Plattner, J., Academic Press, Ch. 12, pp. 121-130 (1998)).
Furthermore, Pgp is also expressed at high levels in the gastrointestinal tract, liver, kidneys, and brain, and therefore Pgp represents a major pharmacological barrier to the bioavailability of many drugs (see Amudkar, et. al in xe2x80x9cBiochemical, Cellular, and Pharmacological Aspects of the Multidrug Transporter,xe2x80x9d Annu. Rev. Pharmacol. Toxicol., 39, pp. 361-398 (1999)). For example, the oral bioavailability of many nutrients and drugs is negatively affected by the action of Pgp present in the gastrointestinal tract. xe2x80x9cOral bioavailabilityxe2x80x9d means the ability of a drug or nutrient that is administered orally to be transported across the gastrointestinal tract and enter into the bloodstream. In addition, Pgp adversely affects penetration of many drugs through the blood-brain barrier.
This invention relates to novel compounds useful in treating or preventing multidrug resistance (xe2x80x9cMDRxe2x80x9d). More specifically, these compounds are useful in treating or preventing P-glycoprotein-mediated MDR and MRP1-mediated MDR. This invention further relates to compositions comprising these compounds. This invention further relates to methods for the preparation and use of the compounds and compositions. The compounds and compositions of this invention are well suited for treatment of multidrug resistant cells, for prevention of the development of multidrug resistance, and for use in multidrug resistant chemotherapies.
Publications and patents are referred to throughout this disclosure. All U.S. Patents cited herein are hereby incorporated by reference.
All percentages, ratios, and proportions used herein are by weight unless otherwise specified.
The following is a list of definitions, as used herein.
xe2x80x9cAromatic groupxe2x80x9d means a group having a monocyclic or polycyclic ring structure. Monocyclic aromatic groups contain 4 to 10 carbon atoms, preferably 4 to 7 carbon atoms, and more preferably 4 to 6 carbon atoms in the ring. Preferred polycyclic ring structures have two or three rings. Polycyclic structures having two rings typically have 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms in the rings. Polycyclic aromatic groups include groups wherein at least one, but not all, of the rings are aromatic.
xe2x80x9cCarbocyclic groupxe2x80x9d means a saturated or unsaturated hydrocarbon ring. Carbocyclic groups are not aromatic. Carbocyclic groups are monocyclic or polycyclic. Polycyclic carbocyclic groups can be fused, spiro, or bridged ring systems. Monocyclic carbocyclic groups contain 4 to 10 carbon atoms, preferably 4 to 7 carbon atoms, and more preferably 5 to 6 carbon atoms in the ring. Bicyclic carbocyclic groups contain 8 to 12 carbon atoms, preferably 9 to 10 carbon atoms in the rings.
xe2x80x9cCarrierxe2x80x9d means one or more substances that are suitable for administration to a subject (i.e., mammal) and that can be combined with the active compound according to this invention. Carrier includes solid and liquid diluents, hydrotropes, surface-active agents, and encapsulating substances.
xe2x80x9cChemosensitizing agentxe2x80x9d means a noncytotoxic compound that sensitizes drug resistant cells to the action of cytotoxic drugs. As used in this application, the term xe2x80x9cchemosensitizing agentxe2x80x9d, excludes the active compounds of this invention.
xe2x80x9cHalogen atomxe2x80x9d means F, Cl, Br, or I.
xe2x80x9cHeteroaromatic groupxe2x80x9d means an aromatic group containing carbon and 1 to 4 heteroatoms in the ring. Monocyclic heteroaromatic groups contain 4 to 10 member atoms, preferably 4 to 7 member atoms, and more preferably 4 to 6 member atoms in the ring. Preferred polycyclic ring structures have two or three rings. Polycyclic structures having two rings typically have 8 to 12 member atoms, preferably 8 to 10 member atoms in the rings. Polycyclic heteroaromatic groups include groups wherein at least one, but not all, of the rings are heteroaromatic.
xe2x80x9cHeteroatomxe2x80x9d means an atom selected from the group consisting of sulfur, phosphorous, nitrogen, and oxygen, e.g., in the ring of a heterocyclic group or the chain of a heterogeneous group. Groups containing more than one heteroatom may contain different heteroatoms.
xe2x80x9cHeterocyclic groupxe2x80x9d means a saturated or unsaturated ring structure containing carbon atoms and 1 or more heteroatoms in the ring. Heterocyclic groups are not aromatic. Heterocyclic groups are monocyclic or polycyclic. Polycyclic heteroaromatic groups can be fused, spiro, or bridged ring systems. Monocyclic heterocyclic groups contain 4 to 10 member atoms (i.e., including both carbon atoms and at least 1 heteroatom), preferably 4 to 7, and more preferably 5 to 6 in the ring. Bicyclic heterocyclic groups contain 8 to 18 member atoms, preferably 9 or 10 in the rings.
xe2x80x9cHeterogeneous groupxe2x80x9d means a saturated or unsaturated chain of non-hydrogen member atoms comprising carbon atoms and at least one heteroatom. Heterogeneous groups typically have 1 to 25 member atoms. Preferably, the chain contains 1 to 12 member atoms, more preferably 1 to 10, and most preferably 1 to 6. The chain may be linear or branched. Preferred branched heterogeneous groups have one or two branches, preferably one branch. Preferred heterogeneous groups are saturated. Unsaturated heterogeneous groups have one or more double bonds, one or more triple bonds, or both. Preferred unsaturated heterogeneous groups have one or two double bonds or one triple bond. More preferably, the unsaturated heterogeneous group has one double bond.
xe2x80x9cHydrocarbon groupxe2x80x9d means a chain of 1 to 25 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 10 carbon atoms, and most preferably 1 to 8 carbon atoms. Hydrocarbon groups may have a linear or branched chain structure. Preferred hydrocarbon groups have one or two branches, preferably 1 branch. Preferred hydrocarbon groups are saturated. Unsaturated hydrocarbon groups have one or more double bonds, one or more triple bonds, or combinations thereof. Preferred unsaturated hydrocarbon groups have one or two double bonds or one triple bond; more preferred unsaturated hydrocarbon groups have one double bond.
xe2x80x9cIC50xe2x80x9d means concentration of drug required to produce a 50% inhibition of growth of cancer cells or 50% inhibition of activity.
xe2x80x9cMDRxe2x80x9d means multidrug resistance.
xe2x80x9cParenteralxe2x80x9d as used herein includes subcutaneous, intravenous, intramuscular, intraarticular, intrasynovial, intrasternal, intrathecal, intrahepatic, intralesional and intracranial injection or infusion techniques.
xe2x80x9cPgpxe2x80x9d means P-glycoprotein.
xe2x80x9cPharmaceutically acceptablexe2x80x9d means suitable for use in a human or other mammal.
xe2x80x9cProtecting groupxe2x80x9d is a group that replaces the active hydrogen of a xe2x80x94OH, xe2x80x94COOH, or xe2x80x94NH2 moiety thus preventing undesired side reaction at the moiety. Use of protecting groups in organic synthesis is well known in the art. Examples of protecting groups are found in Protecting Groups in Organic Synthesis by Greene, T. W. and Wuts, P. G. M., 2nd ed., Wiley and Sons, Inc., 1991. Preferred protecting groups for hydroxyl moieties include silyl ethers, alkoxymethyl ethers, tetrahydropyranyl, tetrahydrofuranyl, esters, and substituted or unsubstituted benzyl ethers. Other preferred protecting groups include carbamates.
xe2x80x9cSubjectxe2x80x9d means a living vertebrate animal such as a mammal (preferably human).
xe2x80x9cSubstituted aromatic groupxe2x80x9d means an aromatic group wherein 1 or more of the hydrogen atoms bonded to carbon atoms in the ring have been replaced with other substituents. Preferred substituents include hydrocarbon groups such as methyl groups and heterogeneous groups including alkoxy groups such as methoxy groups. The substituents may be substituted at the ortho, meta, or para position on the ring, or any combination thereof.
xe2x80x9cSubstituted carbocyclic groupxe2x80x9d means a carbocyclic group wherein 1 or more hydrogen atoms bonded to carbon atoms in the ring have been replaced with other substituents. Preferred substituents include hydrocarbon groups such as alkyl groups (e.g, methyl groups) and heterogeneous groups such as alkoxy groups (e.g., methoxy groups).
xe2x80x9cSubstituted heteroaromatic groupxe2x80x9d means a heteroaromatic group wherein 1 or more hydrogen atoms bonded to carbon atoms in the ring have been replaced with other substituents. Preferred substituents include monovalent hydrocarbon groups including alkyl groups such as methyl groups and monovalent heterogeneous groups including alkoxy groups such as methoxy groups.
xe2x80x9cSubstituted heterocyclic groupxe2x80x9d means a heterocyclic group wherein 1 or more hydrogen atoms bonded to carbon atoms in the ring have been replaced with other substituents. Preferred substituents include monovalent hydrocarbon groups including alkyl groups such as methyl groups and monovalent heterogeneous groups including alkoxy groups such as methoxy groups. Substituted heterocyclic groups are not aromatic.
xe2x80x9cSubstituted heterogeneous groupxe2x80x9d means a heterogeneous group, wherein 1 or more of the hydrogen atoms bonded to carbon atoms in the chain have been replaced with other substituents. Preferred substituents include monovalent hydrocarbon groups including alkyl groups such as methyl groups and monovalent heterogeneous groups including alkoxy groups such as methoxy groups.
xe2x80x9cSubstituted hydrocarbon groupxe2x80x9d means a hydrocarbon group wherein 1 or more of the hydrogen atoms bonded to carbon atoms in the chain have been replaced with other substituents. Preferred substituents include monovalent aromatic groups, monovalent substituted aromatic groups, monovalent hydrocarbon groups including alkyl groups such as methyl groups, monovalent substituted hydrocarbon groups such as benzyl, and monovalent heterogeneous groups including alkoxy groups such as methoxy groups. Substituted hydrocarbon groups include groups wherein a xe2x80x94CH2xe2x80x94 is changed to xe2x80x94C(O)xe2x80x94.
xe2x80x9cSubstrate potentialxe2x80x9d means the likelihood that a compound for use in treating multidrug resistance will be transported out of a cell by cellular transport proteins before effectively preventing or reversing multidrug resistance.
xe2x80x9cTransport proteinxe2x80x9d means a protein that acts to remove cytotoxic substances from cells through the cell membrane. Transport protein includes P-glycoprotein, MRP1, and others.
xe2x80x9cTreating multidrug resistancexe2x80x9d means preventing multidrug resistance from developing in nonresistant cells, increasing or restoring sensitivity of multidrug resistant cells to therapeutic or prophylactic agents, or both.
xe2x80x9cTreatingxe2x80x9d means 1) preventing a disease (i.e., causing the clinical symptoms of the disease not to develop), 2) inhibiting the disease (i.e., arresting the development of clinical symptoms of the disease), 3) relieving the disease (i.e., causing regression of the clinical symptoms), and combinations thereof.
xe2x80x9cWaxxe2x80x9d means a lower-melting organic mixture or compound of high molecular weight, solid at room temperature and generally similar in formulation to fats and oils except that they contain no glycerides.
The active compounds of this invention can have the structure: 
wherein s is an integer from about 1 to about 3. In a preferred embodiment of the invention, s is 1.
A is selected from the group consisting of A1 and A3. Preferably, A is A1.
A1 is a group of the formula: 
wherein  denotes a point of attachment.
Each R1 is independently selected from the group consisting of a hydrogen atom, a hydroxyl group, a hydrocarbon group, a substituted hydrocarbon group, a heterogeneous group, a substituted heterogeneous group, a carbocyclic group, a substituted carbocyclic group, a heterocyclic group, a substituted heterocyclic group, an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group. Preferably, R1 is a hydrogen atom or a hydroxyl group.
R2 is selected from the group consisting of a hydrocarbon group, a substituted hydrocarbon group, a heterogeneous group, a substituted heterogeneous group, a carbocyclic group, a substituted carbocyclic group, a heterocyclic group, a substituted heterocyclic group, an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group.
In a preferred embodiment of the invention, R2 is selected from the group consisting of an aromatic group; a substituted aromatic group; a heteroaromatic group; a substituted heteroaromatic group; a substituted hydrocarbon group, wherein the substituted hydrocarbon group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group; and a substituted heterogenous group, wherein the substituted heterogenous group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group. More preferably, R2 is a substituted hydrocarbon group or a substituted heterogeneous group, wherein said group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group.
In a more preferred embodiment of the invention, R2 is selected from the group consisting of: 
wherein a is at least about 2, b is at least about 2, c is about 1 to about 3, and d is about 1 to about 3. Preferably, a and b are each about 3 to about 10. More preferably, a and b are each about 3.
R12 and R13 are each independently selected from the group consisting of hydrocarbon groups and substituted hydrocarbon groups. Preferably, R12 and R13 are substituted hydrocarbon groups such as alkoxy groups. Preferred alkoxy groups include methoxy, ethoxy, propoxy, and butoxy.
Each R14 is independently selected from the group consisting of CH and a heteroatom. Preferably, the heteroatom is nitrogen. More preferably, each R14 is CH.
D1 and D2 are each independently selected from the group consisting of xe2x80x94C(O)xe2x80x94 and xe2x80x94NR3xe2x80x94, wherein R3 is selected from the group consisting of a hydrogen atom and R2, and with the proviso that optionally, R2 and R3 may be bonded together thereby forming a ring structure selected from the group consisting of heterocyclic groups and substituted heterocyclic groups when D2 is xe2x80x94NR3xe2x80x94.
The ring structure typically has about 4 to about 9 members, preferably 4 to 7 members, more preferably 5 to 6 members. The ring structure is preferably a substituted heterocyclic group, such as substituted piperidyl or substituted piperazinyl. The substituted heterocyclic group is preferably substituted with a group selected from the group consisting of an aromatic group; a substituted aromatic group; a heteroaromatic group; a substituted heteroaromatic group; a substituted hydrocarbon group, wherein the substituted hydrocarbon group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group; and a substituted heterogenous group, wherein the substituted heterogenous group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group.
In a preferred embodiment of the invention, D1 is xe2x80x94C(O)xe2x80x94 and D2 is xe2x80x94NR3xe2x80x94. In this embodiment, preferably, R3 is hydrogen or a hydrocarbon group.
In an alternative embodiment of the invention, D1 is xe2x80x94NR3xe2x80x94 and D2 is xe2x80x94C(O)xe2x80x94. In this embodiment, preferably, R3 is hydrogen or a hydrocarbon group.
In the formula above, x is 0 to about 10, y is 0 or 1, and z is 0 or 1. However, when y is 0; then z is 1. When y is 1; then z is 0. When y is 0 and D1 is xe2x80x94NR3xe2x80x94; then D2 is xe2x80x94C(O)xe2x80x94. When y is 0 and D2 is xe2x80x94NR3xe2x80x94; then D1 is xe2x80x94C(O)xe2x80x94. When x is 0, D1 is xe2x80x94C(O)xe2x80x94, y is 0, D2is xe2x80x94NR3xe2x80x94, and D3 is xe2x80x94C(O)xe2x80x94 or xe2x80x94S(O)2xe2x80x94; then R2 is selected from the group consisting of a hydrocarbon group and a substituted hydrocarbon group, wherein the substituted hydrocarbon group is substituted with an aromatic group.
In an alternative embodiment of the invention, D1 is xe2x80x94C(O)xe2x80x94, y is 1, and z is 0.
A2 is selected from the group consisting of a hydrogen atom and groups of the formula 
wherein u is 0 to about 10, p is 0 to about 10, and v is 0 or 1. Preferably, u is about 1 to about 3. Preferably, p is about 1 to about 3. Preferably, v is 1. More preferably, u is about 1 and p is about 1.
D3 is selected from the group consisting of xe2x80x94S(O)2xe2x80x94, xe2x80x94C(O)xe2x80x94, and xe2x80x94CR1(OH)xe2x80x94. D3 is preferably xe2x80x94CR1(OH)xe2x80x94. However, when D3 is xe2x80x94S(O)2xe2x80x94, then D1 is xe2x80x94C(O)xe2x80x94, D2 is xe2x80x94NR3xe2x80x94, and R2 and R3 are bonded together to form the ring structure.
R5 is selected from the group consisting of a hydrocarbon group, a substituted hydrocarbon group, a heterogeneous group, a substituted heterogeneous group, a carbocyclic group, a substituted carbocyclic group, a heterocyclic group, a substituted heterocyclic group, an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group. However, when D3 is xe2x80x94C(O)xe2x80x94, v is 0, and R5 contains a xe2x80x94C(O)xe2x80x94 group, then p is not 0. Preferably, R5 is selected from the group consisting of substituted hydrocarbon groups of at least 2 carbon atoms and substituted heterogeneous groups of at least 2 member atoms, wherein R5 is substituted with at least one group selected from the group consisting of aromatic groups, heteroaromatic groups, substituted aromatic groups, and substituted heteroaromatic groups;
In a preferred embodiment of the invention, u is 0, and R5 is selected from the group consisting of an aromatic group; a substituted aromatic group; a heteroaromatic group; a substituted heteroaromatic group; a hydrocarbon group; a substituted hydrocarbon group, wherein the substituted hydrocarbon group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group; and a substituted heterogenous group, wherein the substituted heterogenous group is substituted with a group selected from the group consisting of an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group. In one embodiment, preferably p is 0, and D3 is xe2x80x94SO2xe2x80x94. In a more preferred embodiment, D3 is xe2x80x94CR1(OH)xe2x80x94 and R5 is a heteroaromatic group of the formula: 
wherein each X is independently selected from the group consisting of CH and a heteroatom, with the proviso that at least one X is a heteroatom. The heteroatom is preferably nitrogen. Preferably, one X is a heteroatom. Examples of heteroaromatic groups for R5 include quinolyl and isoquinolyl groups. Preferred quinolyl groups for R5 include 4-quinolyl, 5-quinolyl, 6-quinolyl, 7-quinolyl, and 8-quinolyl. More preferably, R5 is 5-quinolyl.
A3 has the formula 
wherein t is about 1 to about 6. Preferably in A3, at least one R1 is a hydroxyl group.
D4 is selected from the group consisting of xe2x80x94C(O)xe2x80x94 and xe2x80x94CHR1xe2x80x94.
D5 is selected from the group consisting of xe2x80x94NR6(R7), xe2x80x94OrR6, and xe2x80x94C(O)R6 wherein r is 0 or 1.
R6 is selected from the group consisting of a hydrocarbon group, a substituted hydrocarbon group, a heterogeneous group, a substituted heterogeneous group, a carbocyclic group, a substituted carbocyclic group, a heterocyclic group, a substituted heterocyclic group, an aromatic group, a substituted aromatic group, a heteroaromatic group, and a substituted heteroaromatic group.
R7 is selected from the group consisting of a hydrogen atom and R6, with the proviso that when u is 0, D3 and D4 are not both xe2x80x94C(O)xe2x80x94.
In a preferred embodiment of the invention, D4 is xe2x80x94C(O)xe2x80x94, t is 0, and D5 is xe2x80x94C(O)R6.
In an alternative preferred embodiment of the invention, D4 is xe2x80x94C(O)xe2x80x94 and D5 is xe2x80x94OrR6.
In an alternative preferred embodiment of the invention, D4 is xe2x80x94CH(R1)xe2x80x94 and D5 is OrR6.
In an alternative preferred embodiment of the invention, D4 is xe2x80x94CH(R1)xe2x80x94 and D5 is xe2x80x94NR6(R7)xe2x80x94.
In an alternative preferred embodiment of the invention, D4 is xe2x80x94C(O)xe2x80x94 and D5 is xe2x80x94xe2x80x94NR6(R7)xe2x80x94.
In an alternative embodiment of the invention, the active compound can be an optical isomer, a diastereomer, an enantiomer, a pharmaceutically-acceptable salt, a biohydrolyzable amide, a biohydrolyzable ester, and a biohydrolyzable imide of the structure.
In one embodiment of the invention, the active compound has the structure above wherein A is A1, R2 and R3 are bonded together and the ring structure has 4 to 6 members in the ring. Examples of compounds according to this embodiment of the invention are shown below in Table 1.
In a preferred embodiment of the invention, the active compound has the structure above wherein A is A1, D1 is xe2x80x94C(O)xe2x80x94, and D2 is xe2x80x94NR3xe2x80x94 where R2 and R3 are not bonded together in a ring structure. Examples of compounds according to this embodiment of the invention are shown below in Table 2.
In an alternative embodiment of the invention, the active compound has the structure above wherein A is A3. An example compound according to this embodiment is shown below in Table 3.
The active compound of this invention inhibits at least one transport protein. The active compound preferably inhibits Pgp or MRP1. More preferably, the active compound inhibits both Pgp and MRP1. In a preferred embodiment of this invention, the active compound inhibits Pgp and has low substrate potential for Pgp. In an alternative preferred embodiment, the active compound inhibits MRP1 and has low substrate potential for MRP1. In the most preferred embodiment of this invention, the active compound inhibits both Pgp and MRP1 and the active compound has low substrate potential for both Pgp and MRP1.
The degree to which a compound inhibits a transport protein can be measured by quantitating the effectiveness of the compound toward restoring drug sensitivity to multidrug resistant cells. Methods for quantitating the effectiveness of the active compounds toward restoring drug sensitivity are readily available to one skilled in the art without undue experimentation (see U.S. Pat. Nos. 5,935,954 and 5,272,159, which are hereby incorporated by reference for the purpose of disclosing these methods). Any assay known to measure the restoration of the anti-proliferative activity of a drug may be employed to test the compounds of this invention. These assays use cell lines resistant to particular drugs, and characterized by the presence of one or both of Pgp and MRP1. These cell lines include L1210, HL60, P388, CHO, and MCF7. Alternatively, resistant cell lines can be developed by methods readily available to one of ordinary skill in the art without undue experimentation (see Chaudhary, et al., xe2x80x9cInduction of Multidrug Resistance in Human Cells by Transient Exposure to Different Chemotherapeutic Agents,xe2x80x9d Journal of the National Cancer Institute, Vol. 85, No. 8, pp. 632-639 (1993)). The cell line is then exposed to compounds of this invention in the presence or absence of the drug to which it is resistant, such as TAXOL(copyright). The viability of the cells treated with both the active compound and the drug can then be compared to the viability of the cells treated only with the drug.
The active compound preferably also has low substrate potential for Pgp or MRP1. More preferably, the active compound has low substrate potential for both Pgp and MRP1. Substrate potential for a transport protein can be determined by using an assay for measuring ATPase activity of the Pgp or MRP1 pumps (see, for example, Reference Example 4, below).
Methods for quantitating accumulation of the active compounds are readily available to one skilled in the art without undue experimentation (see U.S. Pat. No. 5,272,159 which is hereby incorporated by reference for the purpose of disclosing assays for quantitating accumulation). These assays use cell lines resistant to particular chemotherapeutic agents, and characterized by the presence of one or both of Pgp and MRP1. The cell line is exposed to a labeled form of the active compound (e.g., radioactivity or fluorescence labeling) and the accumulation of the active compound is monitored over time. The amount of active compound accumulated in the cell can be compared with a compound which is readily transported by these proteins, e.g. labeled TAXOL(copyright).
This invention further relates to a composition. The composition can be used for treating various conditions or disease states. The composition is preferably a pharmaceutical composition administered for treatment or prevention of multidrug resistance. Standard pharmaceutical formulation techniques are used, such as those disclosed in Remington""s Pharmaceutical Sciences, Mack Publishing Company, Easton, Pa. (1990) and U.S. Pat. No. 5,091,187, which is hereby incorporated by reference.
The composition comprises component (A) the active compound described above and component (B) a carrier. The composition may further comprise component (C) an optional ingredient, such as a therapeutic agent.
Component (B) is a carrier. A carrier is one or more compatible substances that are suitable for administration to a mammal. xe2x80x9cCompatiblexe2x80x9d means that the components of the composition are capable of being commingled with component (A), and with each other, in a manner such that there is no interaction which would substantially reduce the efficacy of the composition under ordinary use situations. Carriers must be of sufficiently high purity and sufficiently low toxicity to render them suitable for administration to the mammal being treated. The carrier can be inert, or it can possess pharmaceutical benefits, cosmetic benefits, or both, depending on the intended use as described herein.
The choice of carrier for component (B) depends on the route by which component (A) will be administered and the form of the composition. The composition may be in a variety of forms, suitable, for example, for systemic administration (e.g., oral, rectal, nasal, sublingual, buccal, or parenteral) or topical administration (e.g., local application on the skin, ocular, liposome delivery systems, or iontophoresis).
Carriers for systemic administration typically comprise one or more ingredients selected from the group consisting of a) diluents, b) lubricants, c) binders, d) disintegrants, e) colorants, f) flavors, g) sweeteners, h) antioxidants, j) preservatives, k) glidants, m) solvents, n) suspending agents, o) surfactants, combinations thereof, and others.
Ingredient a) is a diluent. Suitable diluents include sugars such as glucose, lactose, dextrose, and sucrose; polyols such as propylene glycol; calcium carbonate; sodium carbonate; glycerin; mannitol; sorbitol; and maltodextrin. The amount of ingredient a) in the composition is typically about 1 to about 99%.
Ingredient b) is a lubricant. Suitable lubricants are exemplified by solid lubricants including silica, talc, stearic acid and its magnesium salts and calcium salts, calcium sulfate; and liquid lubricants such as polyethylene glycol and vegetable oils such as peanut oil, cottonseed oil, sesame oil, olive oil, corn oil, and oil of theobroma. The amount of ingredient b) in the composition is typically about 1 to about 99%.
Ingredient c) is a binder. Suitable binders include polyvinylpyrrolidone; magnesium aluminum silicate; starches such as corn starch and potato starch; gelatin; tragacanth; and cellulose and its derivatives, such as sodium carboxymethylcellulose, ethylcellulose, methylcellulose, microcrystalline cellulose, and hydroxypropylmethylcellulose; carbomer; providone; acacia; guar gum; and xanthan gum. The amount of ingredient c) in the composition is typically about 1 to about 99%.
Ingredient d) is a disintegrant. Suitable disintegrants include agar, alginic acid and the sodium salt thereof, effervescent mixtures, croscarmelose, crospovidone, sodium carboxymethyl starch, sodium starch glycolate, clays, and ion exchange resins. The amount of ingredient d) in the composition is typically about 1 to about 99%.
Ingredient e) is a colorant such as an FDandC dye. The amount of ingredient e) in the composition is typically about 1 to about 99%.
Ingredient f) is a flavor such as menthol, peppermint, and fruit flavors. The amount of ingredient f) in the composition is typically about 1 to about 99%.
Ingredient g) is a sweetener such as saccharin and aspartame. The amount of ingredient g) in the composition is typically about 1 to about 99%.
Ingredient h) is an antioxidant such as butylated hydroxyanisole, butylated hydroxytoluene, and vitamin E. The amount of ingredient h) in the composition is typically about 1 to about 99%.
Ingredient j) is a preservative such as phenol, alkyl esters of parahydroxybenzoic acid, benzoic acid and the salts thereof, boric acid and the salts thereof, sorbic acid and the salts thereof, chorbutanol, benzyl alcohol, thimerosal, phenylmercuric acetate and nitrate, nitromersol, benzalkonium chloride, cetylpyridinium chloride, methyl paraben, ethyl paraben, and propyl paraben. Particularly preferred are the salts of benzoic acid, cetylpyridinium chloride, methyl paraben and propyl paraben, and sodium benzoate. The amount of ingredient j) in the composition is typically about 1 to about 99%.
Ingredient k) is a glidant such as silicon dioxide. The amount of ingredient k) in the composition is typically about 1 to about 99%.
Ingredient m) is a solvent, such as water, isotonic saline, ethyl oleate, alcohols such as ethanol, glycerin, cremaphor, glycols (e.g., polypropylene glycol and polyethylene glycol), and buffer solutions (e.g., phosphate, potassium acetate, boric carbonic, phosphoric, succinic, malic, tartaric, citric, acetic, benzoic, lactic, glyceric, gluconic, glutaric, and glutamic). The amount of ingredient m) in the composition is typically about 1 to about 99%.
Ingredient n) is a suspending agent. Suitable suspending agents include AVICEL(copyright) RC-591 from FMC Corporation of Philadelphia, Pa. and sodium alginate. The amount of ingredient n) in the composition is typically about 1 to about 99%.
Ingredient o) is a surfactant such as lecithin, polysorbate 80, sodium lauryl sulfate, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene monoalkyl ethers, sucrose monoesters, lanolin esters, and lanolin ethers. Suitable surfactants are known in the art and commercially available, e.g., the TWEENS(copyright) from Atlas Powder Company of Wilmington, Del. Suitable surfactants are disclosed in the C.T.F.A. Cosmetic Ingredient Handbook, pp. 587-592 (1992); Remington""s Pharmaceutical Sciences, 15th Ed., pp. 335-337 (1975); and McCutcheon""s Volume 1, Emulsifiers and Detergents, North American Edition, pp. 236-239 (1994). The amount of ingredient o) in the composition is typically about 1 to about 99%.
The carrier ingredients discussed above are exemplary and not limiting. One skilled in the art would recognize that different carrier ingredients may be added to or substituted for the carrier ingredients above. One skilled in the art would be able to select appropriate carrier ingredients for systemic compositions without undue experimentation.
Compositions for parenteral administration typically comprise (A) about 0.1 to about 10% of an active compound and (B) about 90 to about 99.9% of a carrier comprising a) a diluent and m) a solvent. Preferably, component a) is propylene glycol and m) is selected from the group consisting of ethanol, ethyl oleate, water, isotonic saline, and combinations thereof.
Compositions for oral administration can have various dosage forms. For example, solid forms include tablets, capsules, granules, and bulk powders. These oral dosage forms comprise a safe and effective amount, usually at least about 1%, and preferably from about 5% to about 50%, of component (A). The oral dosage compositions further comprise (B) about 50 to about 99% of a carrier, preferably about 50 to about 95%.
Tablets can be compressed, tablet triturates, enteric-coated, sugar-coated, film-coated, or multiple-compressed. Tablets typically comprise (A) the active compound, and (B) a carrier comprising ingredients selected from the group consisting of a) diluents, b) lubricants, c) binders, d) disintegrants, e) colorants, f) flavors, g) sweeteners, k) glidants, and combinations thereof. Preferred diluents include calcium carbonate, sodium carbonate, mannitol, lactose, and sucrose. Preferred binders include starch, and gelatin. Preferred disintegrants include alginic acid, and croscarmelose. Preferred lubricants include magnesium stearate, stearic acid, and talc. Preferred colorants are the FDandC dyes, which can be added for appearance. Chewable tablets preferably contain g) sweeteners such as aspartame and saccharin or f) flavors such as menthol, peppermint, and fruit flavors, or both.
Capsules (including time release and sustained release compositions) typically comprise (A) the active compound and (B) the carrier comprising one or more a) diluents disclosed above in a capsule comprising gelatin. Granules typically comprise (A) the active compound, and preferably further comprise k) glidants such as silicon dioxide to improve flow characteristics.
The selection of ingredients in the carrier for oral compositions depends on secondary considerations like taste, cost, and shelf stability, which are not critical for the purposes of this invention. One skilled in the art can optimize appropriate ingredients without undue experimentation.
The solid compositions may also be coated by conventional methods, typically with pH or time-dependent coatings, such that component (A) is released in the gastrointestinal tract at various times to extend the desired action. The coatings typically comprise one or more components selected from the group consisting of cellulose acetate phthalate, polyvinylacetate phthalate, hydroxypropyl methyl cellulose phthalate, ethyl cellulose, acrylic resins such as EUDRAGIT(copyright) coatings (available from Rohm and Haas G.M.B.H. of Darmstadt, Germany), waxes, shellac, polyvinylpyrrolidone, and other commercially available film-coating preparations such as Dri-Klear, manufactured by Crompton and Knowles Corp., Mahwah, N.J. or OPADRY(copyright) manufactured by Colorcon, Inc., of West Point, Pa.
Compositions for oral administration can also have liquid forms. For example, suitable liquid forms include aqueous solutions, emulsions, suspensions, solutions reconstituted from non-effervescent granules, suspensions reconstituted from non-effervescent granules, effervescent preparations reconstituted from effervescent granules, elixirs, tinctures, syrups, and the like. Liquid orally administered compositions typically comprise (A) the active compound and (B) a carrier comprising ingredients selected from the group consisting of a) diluents, e) colorants, and f) flavors, g) sweeteners, j) preservatives, m) solvents, n) suspending agents, and o) surfactants. Peroral liquid compositions preferably comprise one or more ingredients selected from the group consisting of e) colorants, f) flavors, and g) sweeteners.
Other compositions useful for attaining systemic delivery of the active compounds include sublingual, buccal and nasal dosage forms. Such compositions typically comprise one or more of soluble filler substances such as a) diluents including sucrose, sorbitol and mannitol; and c) binders such as acacia, microcrystalline cellulose, carboxymethylcellulose, and hydroxypropylmethylcellulose. Such compositions may further comprise b) lubricants, e) colorants, f) flavors, g) sweeteners, h) antioxidants, and k) glidants.
The composition may further comprise component (C) one or more optional ingredients. Component (C) can be a therapeutic agent used to treat the underlying disease from which the subject suffers. For example, component (C) can be (i) a cancer therapeutic agent, such as a chemotherapeutic agent or a chemosensitizing agent, or a combination thereof; (ii) an antibacterial agent, (iii) an antiviral agent, (iv) an antifungal agent, and combinations thereof. Component (C) can be coadministered with component (A) to increase the susceptibility of the multidrug resistant cells within the subject to the therapeutic agent.
Suitable (i) cancer therapeutic agents are known in the art. Cancer therapeutic agents include chemotherapeutic agents, chemosensitizing agents, and combinations thereof. Suitable chemotherapeutic agents are disclosed in U.S. Pat. No. 5,416,091, which is hereby incorporated by reference for the purpose of disclosing chemotherapeutic agents. Suitable chemotherapeutic agents include actinomycin D, adriyamycin, amsacrine, colchicine, daunorubicin, docetaxel (which is commercially available as TAXOTERE(copyright) from Aventis Pharmaceuticals Products, Inc.), doxorubicin, etoposide, mitoxantrone, mytomycin C, paclitaxel (which is commercially available as TAXOL(copyright) from Bristol-Myers Squibb Company of New York, N.Y.), tenipaside, vinblastine, vincristine, and combinations thereof.
Suitable chemosensitizing agents include calcium channel blockers, calmodulin antagonists, cyclic peptides, cyclosporins and their analogs, phenothiazines, quinidine, reserpine, steroids, thioxantheres, transflupentixol, trifluoperazine, and combinations thereof. Suitable chemosensitizing agents are disclosed by Amudkar, et. al in xe2x80x9cBiochemical, Cellular, and Pharmacological Aspects of the Multidrug Transporter,xe2x80x9dAnnu. Rev. Pharmacol. Toxicol, 39, pp. 361-398 (1999).
Suitable (ii) antibacterial agents, (iii) antiviral agents, and (iv) antifungal agents are known in the art (see xe2x80x9cAnnual Reports on Medicinal Chemistryxe2x80x9433; Section III Cancer and Infectious Diseasesxe2x80x9d ed. Plattner, J., Academic Press, Ch. 12, pp. 121-130 (1998)). Suitable antibacterial agents include quinolones, fluoroquinolones, xcex2-lactam antibiotics, aminoglycosides, macrolides, glycopeptides, tetracyclines, and combinations thereof.
Suitable (iii) antiviral agents include protease inhibitors, DNA synthase inhibitors, reverse transcription inhibitors, and combinations thereof.
Suitable (iv) antifungal agents include azoles, such as ketoconazole, fluconazole, itraconazole, and combinations thereof.
One skilled in the art will recognize that these therapeutic agents are exemplary and not limiting, and that some may be used in the treatment of various multidrug resistant conditions and diseases. One skilled in the art would be able to select therapeutic agents without undue experimentation.
The amount of component (C) used in combination with component (A), whether included in the same composition or separately coadministered, will be less than or equal to that used in a monotherapy. Preferably, the amount of component (C) is less than 80% of the dosage used in a monotherapy. Monotherapeutic dosages of such agents are known in the art.
Component (C) may be part of a single pharmaceutical composition or may be separately administered at a time before, during, or after administration of component (A), or combinations thereof.
In a preferred embodiment, the composition of this invention comprises component (A), component (B), and (C) a chemotherapeutic agent. In an alternative preferred embodiment, the composition comprises component (A), component (B), and (C) a chemosensitizing agent. In another preferred alternative embodiment, the composition comprises component (A), component (B), and (C) both a chemotherapeutic agent and a chemosensitizing agent.
The exact amounts of each component in the systemic compositions depend on various factors. These factors include the specific compound selected as component (A), and the mode by which the composition will be administered. The amount of component (A) in the systemic composition is typically about 1 to about 99%.
The systemic composition preferably further comprises 0 to 99% component (C), and a sufficient amount of component (B) such that the amounts of components (A), (B), and (C), combined equal 100%. The amount of (B) the carrier employed in conjunction with component (A) is sufficient to provide a practical quantity of composition for administration per unit dose of the compound. Techniques and compositions for making dosage forms useful in the methods of this invention are described in the following references: Modern Pharmaceutics, Chapters 9 and 10, Banker and Rhodes, eds. (1979); Lieberman et al., Pharmaceutical Dosage Forms: Tablets (1981); and Ansel, Introduction to Pharmaceutical Dosage Forms, 2nd Ed., (1976).
Topical compositions comprise: component (A), described above, and component (B) a carrier. The carrier of the topical composition preferably aids penetration of component (A) into the skin. Topical compositions preferably further comprise (C) the optional ingredient described above.
Component (B) the carrier may comprise a single ingredient or a combination of two or more ingredients. In the topical compositions, component (B) is a topical carrier. Preferred topical carriers comprise one or more ingredients selected from the group consisting of water, alcohols, aloe vera gel, allantoin, glycerin, vitamin A and E oils, mineral oil, propylene glycol, polypropylene glycol-2 myristyl propionate, dimethyl isosorbide, combinations thereof, and the like. More preferred carriers include propylene glycol, dimethyl isosorbide, and water.
The topical carrier may comprise one or more ingredients selected from the group consisting of q) emollients, r) propellants, s) solvents, t) humectants, u) thickeners, v) powders, and w) fragrances in addition to, or instead of, the preferred topical carrier ingredients listed above. One skilled in the art would be able to optimize carrier ingredients for the topical compositions without undue experimentation.
Ingredient q) is an emollient. The amount of ingredient q) in the topical composition is typically about 5 to about 95%. Suitable emollients include stearyl alcohol, glyceryl monoricinoleate, glyceryl monostearate, propane-1,2-diol, butane-1,3-diol, mink oil, cetyl alcohol, isopropyl isostearate, stearic acid, isobutyl palmitate, isocetyl stearate, oleyl alcohol, isopropyl laurate, hexyl laurate, decyl oleate, octadecan-2-ol, isocetyl alcohol, cetyl palmitate, di-n-butyl sebacate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, butyl stearate, polyethylene glycol, triethylene glycol, lanolin, sesame oil, coconut oil, arachis oil, castor oil, acetylated lanolin alcohols, petrolatum, mineral oil, butyl myristate, isostearic acid, palmitic acid, isopropyl linoleate, lauryl lactate, myristyl lactate, decyl oleate, myristyl myristate, polydimethylsiloxane, and combinations thereof. Preferred emollients include stearyl alcohol and polydimethylsiloxane.
Ingredient r) is a propellant. The amount of ingredient r) in the topical composition is typically about 5 to about 95%. Suitable propellants include propane, butane, isobutane, dimethyl ether, carbon dioxide, nitrous oxide, nitrogen, and combinations thereof.
Ingredient s) is a solvent. The amount of ingredient s) in the topical composition is typically about 5 to about 95%. Suitable solvents include water, ethyl alcohol, methylene chloride, isopropanol, castor oil, ethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, dimethylsulfoxide, dimethyl formamide, tetrahydrofuran, and combinations thereof. Preferred solvents include ethyl alcohol.
Ingredient t) is a humectant. The amount of ingredient t) in the topical composition is typically about 5 to about 95%. Suitable humectants include glycerin, sorbitol, sodium 2-pyrrolidone-5-carboxylate, soluble collagen, dibutyl phthalate, gelatin, and combinations thereof. Preferred humectants include glycerin.
Ingredient u) is a thickener. The amount of ingredient u) in the topical composition is typically 0 to about 95%.
Ingredient v) is a powder. The amount of ingredient v) in the topical composition is typically 0 to about 95%. Suitable powders include chalk, talc, fullers earth, kaolin, starch, gums, colloidal silicon dioxide, sodium polyacrylate, tetraalkyl ammonium smectites, trialkyl aryl ammonium smectites, chemically modified magnesium aluminum silicate, organically modified montmorillonite clay, hydrated aluminum silicate, fumed silica, carboxyvinyl polymer, sodium carboxymethyl cellulose, ethylene glycol monostearate, and combinations thereof.
Ingredient w) is a fragrance. The amount of ingredient w) in the topical composition is typically about 0.001 to about 0.5%, preferably about 0.001 to about 0.1%.
Ingredient x) is a wax. Waxes useful in this invention are selected from the group consisting of animal waxes, vegetable waxes, mineral waxes, various fractions of natural waxes, synthetic waxes, petroleum waxes, ethylenic polymers, hydrocarbon types such as Fischer-Tropsch waxes, silicone waxes, and mixtures thereof wherein the waxes have a melting point between 40 and 100xc2x0 C. The amount of ingredient x) in the topical composition is typically about 1 to about 99%.
In an alternative embodiment of the invention, the active compounds may also be administered in the form of liposome delivery systems, such as small unilamellar vesicles, large unilamellar vesicles, and multilamellar vesicles. Liposomes can be formed from a variety of phospholipids, such as cholesterol, stearylamine or phosphatidylcholines. A preferred composition for topical delivery of the present compounds uses liposomes as described in Dowton et al., xe2x80x9cInfluence of Liposomal Composition on Topical Delivery of Encapsulated Cyclosporin A: I. An in vitro Study Using Hairless Mouse Skinxe2x80x9d, S.T.P. Pharma Sciences, Vol. 3, pp. 404-407 (1993); Wallach and Philippot, xe2x80x9cNew Type of Lipid Vesicle: Novasome(copyright)xe2x80x9d, Liposome Technology, Vol. 1, pp. 141-156 (1993); U.S. Pat. Nos. 4,911,928, and 5,834,014.
The exact amounts of each component in the topical composition depend on various factors. Including the specific compound selected for component (A) and the mode by which the composition will be administered. However, the amount of component (A) typically added to the topical composition is about 0.1 to about 99%, preferably about 1 to about 10%.
The topical composition preferably further comprises 0 to about 99% component (C), more preferably 0 to abut 10%, and a sufficient amount of component (B) such that the amounts of components (A), (B), and (C), combined equal 100%. The amount of (B) the carrier employed in conjunction with component (A) is sufficient to provide a practical quantity of composition for administration per unit dose of the compound. Techniques and compositions for making dosage forms useful in the methods of this invention are described in the following references: Modern Pharmaceutics, Chapters 9 and 10, Banker and Rhodes, eds. (1979); Liebermnan et al., Pharmaceutical Dosage Forms: Tablets (1981); and Ansel, Introduction to Pharmaceutical Dosage Forms, 2nd Ed., (1976).
Topical compositions that can be applied locally to the skin may be in any form including solutions, oils, creams, ointments, gels, lotions, shampoos, leave-on and rinse-out hair conditioners, milks, cleansers, moisturizers, sprays, skin patches, and the like. Component (A) may be included in kits comprising component (A), a systemic or topical composition described above, or both; and information, instructions, or both that use of the kit will provide treatment for multidrug resistance (particularly in humans). The information and instructions may be in the form of words, pictures, or both, and the like. In addition or in the alternative, the kit may comprise component (A), a composition, or both; and information, instructions, or both, regarding methods of administration of component (A) or the composition, preferably with the benefit of treating multidrug resistance in mammals.
In an alternative embodiment of the invention, components (A) and (C) may be included in kits comprising components (A) and (C), systemic or topical compositions described above, or both; and information, instructions, or both that use of the kit will provide treatment for multidrug resistance (particularly humans). The information and instructions may be in the form of words, pictures, or both, and the like. In addition or in the alternative, the kit may comprise components (A) and (C), compositions, or both; and information, instructions, or both, regarding methods of administration of components (A) and (C) or the compositions, preferably with the benefit of treating multidrug resistance in mammals.
This invention relates to a method for inhibiting transport protein activity. The method comprises administering to a subject (A) an active compound described above.
This invention further relates to a method for treating multidrug resistance. The method comprises administering to a subject (preferably a human) suffering from multidrug resistance, (A) an active compound described above. For example, a subject diagnosed with multidrug resistant cancer can be treated by the methods of this invention. Preferably, a systemic or topical composition comprising (A) the active compound and (B) the carrier is administered to the subject. More preferably, the composition is a systemic composition comprising (A) the active compound, (B) the carrier, and (C) an optional ingredient such as a therapeutic agent. Component (A) may be administered before, during, or after administration of component (C). A preferred administration schedule is a continuous infusion over the 24 hour period during which component (C) is also administered.
The dosage of component (A) administered depends on various factors, including the method of administration, the physical attributes of the subject (e.g., age, weight, and gender), and the condition from which the subject suffers. Effective dosage levels for treating or preventing MDR range from about 0.01 to about 100 mg/kg body weight per day, preferably about 0.5 to about 50 mg/kg body weight per day of (A) a compound of this invention. These dosage ranges are merely exemplary, and daily administration can be adjusted depending on various factors. The specific dosage of the active compound to be administered, as well as the duration of treatment, and whether the treatment is topical or systemic are interdependent. The dosage and treatment regimen will also depend upon such factors as the specific active compound used, the treatment indication, the efficacy of the active compound, the personal attributes of the subject (such as, for example, weight, age, sex, and medical condition of the subject), compliance with the treatment regimen, and the presence and severity of any side effects of the treatment.
In addition to the benefits in treating multidrug resistance in subjects suffering from cancer, the active compounds in the compositions and methods of this invention can also be used to treat other conditions. These other conditions include other types of multidrug resistance (i.e., in addition to cancer multidrug resistance) such as bacterial, viral, and fungal multidrug resistance. For example, many of the FDA approved HIV protease inhibitors used to treat AIDS patients suffering from the HIV virus are substrates for Pgp. Therefore, in an alternative embodiment of this invention, an active compound of this invention is coadministered with a therapeutic agent such as an HIV protease inhibitor.
The active compounds and compositions of this invention can also be administered with other therapeutic agents such as oral drugs. The active compounds and compositions can be used to enhance oral drug absorption and increase bioavailability of various drugs.
The active compounds and compositions can also be used to aid drug delivery through the blood-brain barrier for, e.g., enhancing the effectiveness of drugs to treat Alzheimer""s disease, treating memory disorders, enhancing memory performance, or treating any other central nervous system disorder where drug delivery is compromised via this transport pump mechanism.
The active compounds and compositions can also be administered to treat subjects suffering from neurological disorders such as spinal injuries, diabetic neuropathy, and macular degeneration.
The active compounds and compositions can also be administered to treat subjects suffering from vision disorders and to improve vision.
The active compounds and compositions can also be administered to treat hair loss. xe2x80x9cTreating hair lossxe2x80x9d includes arresting hair loss, reversing hair loss, and promoting hair growth.
The active compounds and compositions can also be adminstered to treat inflammatory diseases. Inflammatory diseases include irritable bowel disease, arthritis, and asthma.